Re: mod function and division

From: Tom St Denis (tom_at_securescience.net)
Date: 03/30/04 

Date: Mon, 29 Mar 2004 23:26:14 GMT

dahlia wrote:

> a simple question for this illustrious group:
>
> what is the fastest way ( algorithm ) to find out if  big numbers( hundred
> of digits )  N(i) are divisible by a small number below 100 ( say 37 )? do
> we do the divisions or do we use the mod function?

You need not any "hard" form of divisions.  You need only a "digit shift",
multiplication and addition/subtraction.

I'd tell you about a free text book on math that covers this topic but
apparently the concensus here is that the book isn't worthy.

Tom

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